The sport of bungee jumping is becoming increasingly popular. When practicing the sport, an individual wears a harness attached to an end of an elastic cord, the other end of the elastic cord being attached to an elevated structure. The bungee jumper, while the elastic cord is slack, jumps from an elevated position. The length of the elastic cord, or bungee cord as it is commonly known, is such that it stretches at the end of the fall to arrest the downward movement of the jumper. The inherent resiliency of the elastic cord then causes upward rebound of the jumper.
It is known to incorporate braiding along the length of an elastic cord to surround and protect the inner elastic cord (which may be single strand or multi-strand) and to function as a safety back-up in the event of elastic strand breakage. Such braiding, to some degree at least, functions as a support for a suspended bungee jumper in the event of elastic strand breakage or failure. The braiding also operates to limit the degree of stretching of the elastic cord; however, the braiding does not act as a positive restraint, instead permitting stretch of the cord with which it has been combined over a considerable, and relatively unpredictable, range. Thus, there is no absolute assurance that a jumper's downward motion will be terminated in a predictable manner by the braiding.
Another difficulty inherent in the use of braiding in operative association with an elastic cord employed as a bungee or shock cord, is the fact that the inner elastic strand or strands are always under tension. That is, braiding stresses the elastic strands with which it is associated at all times even when the strands are not stretched. Of course, when stretching does occur due to normal use of the shock cord, such stress becomes even greater. This can shorten the operating life of the cord adversely affect its performance.